This is my first post to your forum. I am the developer of Hyperion-Mesh3D which is a volume based hexahedral meshing tool. I am releasing this tool as freeware. In order to increase the usage and exposure of Mesh3D, I realized that I would need to create a neutral file export format to support OpenFoam.

Currently Mesh3D can export to a NASTRAN BDF format (CHEXA) in addition to other tool-specific formats, e.g. Hyperion-TFS and Ansys-TAS. However, I was not able to discern what format is applied in the OpenFoam CFD tool.

Perhaps someone could point to posts or guidance for a format that would best work with the Foam tool set. I could adopt this and add it to the export format dialog in Mesh3D.

It will be really nice to use mesh3d for OF projects. Is mesh3d released as freeware now?

I work on conjugate heat transfer projects with both fluid elements and solid elements. Does mesh3d support different elements type?

Pei

olesen

February 8, 2008 04:39

Dean,
Your program sounds l

Dean,

Your program sounds like it could be interesting. I'm curious to take a peak and see how it handles prism (boundary) layers. I also hope it is possible to define the boundary regions within your tool, since this is an often ignored aspect.

Since your mesh is pure hexa, it might the easiest to export into another format for which there is already a converter. eg, ideasUnvToFoam, fluentMeshToFoam, starToFoam. This might also provide a broad spectrum of potential users.

I don't know where the Fluent format is documented, but I can provide you information about the STAR-CD format. I also have a PDF about the ideas unv format. The unv format might be a good one anyhow, since the FEA people can probably use it too.

As a final note: I noticed from your web page that there is a 32bit windows installer. A Linux version would be extremely welcome, since this is the main platform in use by the OpenFOAM community.

/mark

vinz

February 8, 2008 05:00

Dear Dean,
As the others po

Dear Dean,

As the others pointed out, your program looks very interesting especially for complex meshes.
A while ago, I made a converter from GridPro to OpenFOAM. Even if I don't know the type of files you generate with your program, GridPro being a hexaedral mesher as well, it could help to have a look at this converter.
You'll see that it's not so difficult, and I hope you'll find a way to make this program available for OpenFOAM users.
Good luck,

Vincent

titan_algorithms

February 8, 2008 06:04

All,
Hyperion Mesh3D and TF

All,

Hyperion Mesh3D and TFS install in demo mode. Simply follow the instructions to request a codekey. I may disable this in the future. However, I will issue codekeys which release the codes to Full use mode, of course for free. All of our the products contain absolutely no spyware. The codekey just locks the code (major and minor rev) to the drive serial number. At present since I will release it free, it is just to keep a handle on who has copies (through the signup) and to make sure nobody starts unauthorized reselling.

The current grid-brick format for TFS exports looks to be close to OpenFoam:

The cell shapes described in OpenFOAM are only to help with mapping to/from conventional meshes. There is no "neutral" OpenFOAM format, but just the polyMesh. Here you have a few files: "points", "faces", "owner" and "neighbour".

Each mesh face is described by a list of points and has an owner (outward facing normal) and a neighbour (inward facing normal). Faces without any neighbours are boundary faces.

I've submitted my contact information via your web site if you wish to take this off-forum.

It is really unfortunate that it is a Windows-only program.

/mark

titan_algorithms

February 8, 2008 07:08

Hi Mark
The hex mesh is nat

Hi Mark

The hex mesh is naturally equivalenced in Mesh3D. that is, if there is a i+1x neighbor on the hex,then it shares the grids on the +x face, e.g. 2 3 and 5 6.

@windows: I just tried the program in Wine on my Linux-machine and it seems to work fine

@format: The structure of the format (not the syntax) looks quite similar to the format that the gambitToFoam converter reads (except that it only does hex and there are no boundary patches defined) so one might use that as a starting point for a converter.

Bernhard

titan_algorithms

February 8, 2008 09:41

to note, boundary patches are

to note, boundary patches are known in the Mesh3D code, e.g. see menu selection for display CS (control surface, same as BC). This could be captured pretty easily.

hsieh

February 8, 2008 13:42

Hi, Dean,
By element type,

Hi, Dean,

By element type, I mean, if handles as ONE mesh, then, the elements in the mesh consists of solid elements (may have different material properties) and fluid elements.

Another possibility is dual-meshing, ie. one mesh for fluid and one mesh for solids. In the solid mesh, there might be several regions for each solid material. Ideally, the common surfaces between fluid and solids have idential nodes (conforming).

Pei

titan_algorithms

February 9, 2008 06:16

Hi Pei
I think this might h

Hi Pei

I think this might help with your question. I believe you can do some of what you are looking for. Consider this tutorial:

Basically it shows a fin bank which is meshed. The fin mesh is cut from edge detection and can be exported first or last and is basically the conjugate of the flow mesh.

I will try to work up an example for you to show you how this could be done.

do you have any candidate geometry (stl, dxf, obj)?

Regards, D

titan_algorithms

February 9, 2008 06:23

Pei
in this example, you wi

Pei

in this example, you will see two project files (.m3d). One is labeled EDGE and one is labeled FILL. Both form an equivalenced mesh. Note this is a coarse mesh designed to demonstrate the flow conductor option in TFS. You can refine the mesh block and perform the same export option, but remember to process the voxel selection identically for both models.

D

titan_algorithms

February 9, 2008 09:21

Here I worked up a an example

Here I worked up a an example of a casting. I need to modify this slightly but this should convey the concept. You create a voxel space, then cut the EDGE or FILL or combinations, e.g. BLOCK NOT FILL.